Answer to Question 1
Protein is part of human muscles, skin, hair, and nails. It supports growth and maintenance of cells, as well as formation of enzymes, hormones, and antibodies. Protein also plays an important role in regulating fluid and acidbase balance. The major sources of protein are meat and meat products, dairy, grains, and vegetables. Essential amino acids are amino acids that the body requires but cannot produce on its own. Thus, they must come from food sources. A complete protein is a food that contains all of the essential amino acids. Incomplete proteins are foods that are missing one or more of the essential amino acids. When people do not get good sources of complete protein, they can combine incomplete proteins to receive all the amino acids they need. These combined proteins are called complementary proteins. Examples include peanut butter on whole-wheat bread or red beans and rice. An excessive amount of protein can cause weight gain and loss of minerals. Insufficient protein consumption harms muscles, skin, hair, and basic body
functions. Eventually, loss of protein will harm the major muscle: the heart.
Answer to Question 2
A
Elastic fibres are made of elastin, one type of structural protein found in the ECM of animal cells
Erythrocytes contain large amounts of the oxygen-transporting protein
Sources of Energy in the United States
The Ear and Its Functions
Initiation of protein biosynthesis in prokaryotes
The Fate of Amino Acids in Your Body